Toothbrush



R. G. BACKSTROM TOOTHBRUSH Filed Jan. 12, 1951 INVENTOR.

Fosa-Afr Gt .Bachs/wam Patented Oct. 5, 1954 UNITED sTATss PATENTOFFICEv TAOTHBRUSH Robert G. Backstrom, Palm Springs, Calif.yApplication January 12, 195,1, Serial No. 205,698

l (el. 15-167) 1 Claim.

This invention relates to toothbrushes and more particularly to atoothbrush especially shaped to fit the human dental arch.

It is among the objects of the invention to provide an improvedtoothbrush especially shaped to fit the human dental arch and apply itsbristles to all accessible surfaces of the teeth constituting such anarch; which includes a handle of a size and shape to provide a firm andcomfortable grip for a person using the brush; which includes bristletufts so directed relative to the brush back and handle as to contactall accessible surfaces of the teeth and remove food deposits therefromduring the brushing operation; and which is simple and durable inconstruction, economical to manufacture, easy to use, and neat andattractive in appearance.

Other objects and advantages will become apparent from a considerationof the following description and the appended claim in conjunction withthe accompanying drawing wherein:

Figure l is a side elevational view of a toothbrush illustrative of theinvention shown in operative association with a human dental archdiagrammatically illustrated in brokenlines;

Figure 2 is a bottom plan view of thev toothbrush illustrated in Figure1; and

Figure 3 is a transverse cross sectional view on the line 3-3 of Figurel.

With continued reference to the drawing, the brush comprises anelongated body, generally indicated at I0, formed of a suitable rigidand preferably slightly resilient material, such as synthetic resinplastic, natural or synthetic rubber or an inorganic material, andbristle tufts, generally indicated at II, secured each at one end in thebody I0 near one end of the latter and projecting from one face orsurface of the body in spaced apart relationship to each other.

The body I 0 includes a handle I2, a brush back I3 at one end of thehandle and a neck I4 disposed between the handle and the brush back andis longitudinally curved on a fiat arc with the surface of the brushback I3 from which the bristles extend and the surfaces of the neck I4and handle I2 at the same side of the body substantially in a commonarcuate surface.

The handle I2 is of generally rectangular cross sectional shape andtapers arcuately in a direction toward the neck I4. It has four concavesurfaces extending longitudinally thereof, as indicated at I5, I6, Iland VI8 providing therebetween four outwardly projecting, rounded ribsor ridges I9, 20, 2| and 22 which give a firm grip on the handle andprevent the handle from turn- 2 ing in the hand of the user even thoughthe handle is wet. This also provides a structure cf maximum rigidityconsistent with the weight and size of the handle so that thelongitudinally curved shape of the handle will be retained during use ofthe toothbrush.

The neck I4 is of rounded shape and tapers in a direction away from thehandle and in a direction away from the adjacent end of the brush backI3 so that its minimum cross sectional area is intermediate the lengththereof but somewhat nearer the brush back than the handle.

The brush back I3 has a substantially fiat face cr surface from whichthe bristles II extend and is convexly rounded on its opposite side. Thebrush back tapers in a direction away from the neck I4 and terminates ina rounded formation at its distal end.

The brush back I3 is 0i sufient rigidity to hold the bristle tufts inthe proper direction relative to the handle, but the neck I4 is somewhatmore resilient than either the handle or the brush back so that thebrush back can move slightly relative to the handle when subjected topressure.

The bristle tufts are arranged in two rows disposed one row along eachopposite side of the brush back I3 and the tufts in the two rows arepreferably staggered relative to each other, as is particularlyillustrated in Figure 2. The bristle tufts are inclined slightly in adirection away from the surface of the brush back I3 from which theyextend and away from the handle Il! so that the distal ends of thebristles will be forced deeply into the spaces between the teeth as thebrush is moved across the surfaces of the teeth, as is particularlyillustrated in Figure l.

The bristles from which the tufts II are formed may be either animalbristles or synthetic bristles of known composition or construction andthe bristle tufts are received at their small ends in correspondingapertures provided in the brush back and secured in these apertures in adesired or Well known manner.

Near its end remote from the neck I4 the handle I2 is provided with atransversely extending aperture 23 which aperture may receive a fixedpeg or hook for suspensively supporting the toothbrush, when desired.

It will be noted that the bristle tufts II decrease in length in adirection from the tufts at the distal end of the brush back I3 towardthe neck I4 so that the outer ends of the tufts are disposed adjacent aplane which intersects the member I0 substantially at the juncturebetween the handle I2 and the neck I4 and is disposed at an acute angleto the adjacent surface of the neck. This arrangement also assists inpositioning the bristle tufts so that the bristles will be forced deeplyinto the spaces between the teeth to clean out food deposits in thesespaces.

The invention may be embodied in other specic forms without departingfrom the spirit or essential characteristics thereof. The presentembodiment is, therefore, to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claim rather than by the foregoingdescription, and all changeswhich come within the meaning and range ofequivalency of the claim are, therefore, intended to be embracedtherein.

What is claimed is:

In a toothbrush, an elongated body including a handle at one end, a neckintermediate its ends, and a brush back at its other end, said handlebeing generally rectangular in cross section and tapering arcuately in adirection toward the neck, the several sides of said handle beingtransversely concaved with the concave surfaces of the handle extendinglongitudinally thereof for the full length of the handle, said concavesurfaces providing therebetween outwardly projecting, rounded ribsextending the length of the handle, said neck being of rounded crosssection and tapering in a direction away from the handle and in adirection away from the adjacent end of the brush back to locate theminimum cross sectional area of the neck intermediate thereof, saidminimum cross sectional area of the neck being nearer the brush backthan the handle, said brush back having a substantially at bristle faceand having its outer face transversely convexed, said brush backdecreasing progressively in thickness fully from end to end in thedirection of the distal end thereof while remaining constant in widththroughout its length, the brush back having itsv outer surface disposedsubstantially in a plane arranged at acute angles to the plane of itsbristle face; and parallel rows of bristle tufts secured to said backwith the tufts of each row extending outwardly from the bristle face ofthe brush back, said tufts decreasing progressively in length in adirection away from the distal end of the brush back with their outerends terminating in a plane approximately paralleling that of the outersurface of the brush back and intersecting the body substantially at thejuncture between the handle and neck, with said plane of the outer endsof the bristle tufts being disposed at an acute angle to the adjacentsurface of said neck, said body being longitudinally curved on a at arcwith said bristle face of the brush back and those surfaces of thehandle and neck disposed at the same side of the body as the bristleface lying substantially in a common arcuate surface, the respectivebristle tufts being inclined slightly out of perpendicularity to theplane in which the outer ends thereof are disposed with the direction ofinclination, when taken from the inner to the outer ends of said tufts,being toward the distal end of the brush back.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 28,794 Wadsworth June 19, 1860 306,776 Rhein Oct. 2l, 1884335,345 Estabrook Feb. 2, 1886 758,764 MacLeod May 3, 1904 958,371 DanekMay 17, 1910 1,500,722 Roush July 8, 1924 2,130,661 Zaebst Sept. 20,1938 2,274,042 Cosby Feb. 24, 1942 2,304,319 Saltzman Dec. 8, 19422,483,503 Pollack Oct. 4, 1949 FOREIGN PATENTS Number Country Date19,408 Great Britain of 1896 558,864 France Sept. 4, 1924

